Some cellular networks comprise multiple layers of cells of different classes, e.g., macro cells, microcells, picocells and/or femtocells. Such networks are sometimes referred to as heterogeneous networks. The multi-layer network structure affects the interference experienced by communication terminals. Several techniques are known in the art for reducing interference in heterogeneous networks.
For example, 3GPP Technical Specification Group Radio Access Network (TSG-RAN) WG1 document R1-103561, entitled “Improving Control Reliability in Severe Interference Conditions,” Dresden, Germany, Jun. 28-Jul. 2, 2010, which is incorporated herein by reference, describes Time Division Multiplexing (TDM) scheduling schemes for improving the reliability of downlink control channels using sub-frame partitioning. TDM scheduling schemes of this sort are further analyzed in TSG-RAN WG1 document R1-104817, entitled “Analysis of Solutions to Improve Control Reliability in Severe Interference Conditions,” Madrid, Spain, August 23-27, which is incorporated herein by reference. Example TDM scheduling patterns for heterogeneous networks are also proposed in TSG-RAN WG1 document R1-105336, entitled “On Data Channel Performance with Cell Range Expansion and Non-Full Buffer Traffic,” which is incorporated herein by reference.
As another example, techniques for reducing interference by inter-cell interference coordination (ICIC) are described, for example, in section 16.1.5 of 3GPP Technical Specification TS 36.300, entitled “Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description,” (3GPP TS 36.300, version 11.7.0, Release 11), September, 2013, which is incorporated herein by reference.
The description above is presented as a general overview of related art in this field and should not be construed as an admission that any of the information it contains constitutes prior art against the present patent application.